Motor-controller



R. B. HUNTER.

MOTOR CONTROLLER. APPLICATION FILED MAR. 19. 1917 .latented June 10, 1919.

UNITED STATES PATENT OFFICE.

RICHARD B. HUNTER, or MILWAUKEE, wIsooNsIN, A.SSIGNOR TO THE CUTLER- HAMMER MFG 00., or MILWAUKEE, WISCONSIN, A CORPORATION or WISCONSIN.

Moron-CONTROLLER.

Specification of Letters Patent.

Patented June 10, 1919.

Application filed. March 19, 1917. Serial No. 155,738.

- T all whom it may concern:

Be it known that I, RICHARD B. HUNTER, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Motor-Controllers, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

This invention relates to motor controllers and is particularly applicable to controllers for motor-driven washing machines although it is not limited thereto,

An object of the invention 15 to provide a controller wherein the motor acceleratlng means requires resetting for successive operations thereof, with means enabling starting of the motor free from accelerating influence by the former means after stopping of said motor without resetting of the accelerating means. I

Other objects and advantages of the 1nvention will hereinafter appear.

The accompanying drawing illustrates one embodiment of the invention and the same will vnow be described, it being understood that the invention is susceptible of embodiment in other forms falling within the scope of the appended claims.

The controller selected for illustration'is utilized to control a shunt motor M having an armature a and a shunt field winding 7, said controller providing for acceleration of the motor through the medium of parallel resistances 'r, 4", and 7'.

In brief, the controller includes an electromagnetic main switch 1 controlling the continuity of the motor circuit, a push button switch 2 controlling said main switch, an accelerating device 3 illustrated schematically as of the drum type, and an electromagnetic switch 4 controlling the effectiveness of the device 3.

The device 3 comprises a series of contacts 5 to 10 and a series of cooperating contact segments 5 to 10*; The segments 5 and 6 are electrically connected and are adapted upon engagement with contacts 5 and 6 to complete themotor circuit through the main resistance r and said segments are of such length as to engage their respective contacts in all but the oii' position ofthe device. Segments 7 to 10 are electrically interconnected but are electrically independent of segments 5 and 6 Segments 7* and 10 are adapted to simultaneously engage their respective contacts to complete the circuit of resistance 0* in the second operative position of the device, while the segment 8 is engageable with its contact to complete the circuit of resistance 1- in the third operative position of the device, and segment 9 is engageable with its contact to short-circuit all of the resistances in the fourth operative position of the device. However, all of the last mentioned circuits are dependent upon the switch 4:, as will appear.

The switch 4 is included in series with the contacts 10 and 10 of the accelerating dev1ce and is biased to open position whereby its closure is essential to accelerating action of said device. This switch is provided with an operating winding connected in shunt with the field f of the motor, to be energized upon closure of main switch 1. Also,'this switch is provided with a lockout winding 4" connected in series with the armature of the motor and designed to restrain the switch 4 against response at a very low current value. The switch, however, is free to respond without restraint by the winding 49 when the device 3 is in oif position, as shown, and its operating winding is designed to insure retention thereof in closed position upon subsequent energization of the winding 4 Thus assuming the device 3 to occupy any of its operative positions with the swltches 1 and 4 open, it will be observed that the motor circuit may be closed by the switch 1 and that the switch 4 will be held in open position by its winding 4", thereby forcing the motor current to traverse the main resistance 9. Then assuming return of the device 3 to 01f position, the same will open the motor circuit, thereby deenergizing the lookout winding P of switch 4, allowing said switch to close, assuming retention of the switch 1 in closed position or subsequent closure thereof with the device 3 in the cit position. Thereupon the device 3 may be again operated to accelerate the motor to normal speed.

Tracing the circuits, that of the motor armature extends from line L through switch 1, by conductor 11 through said arconductor 17 through said winding to con-.

ductor 16. Then assuming the device 3 to occupy its second operative position and further assuming the switch 4 to be closed, circuit may be traced from the right hand terminal of the motor armature through resistance rto contact 7 and segment 7 thence to segment 10 and contact 10, by conductor 18 through switch 4, by conductor 13to line L, thereby paralleling resistances 1' and 1-.

Then assuming the device 3 to occupy its third operative position, circuit may be traced from theright hand terminal of the motor armature through resistance r to contact 8 and segment 8., thence to segment 10* and line L as already traced, thereby paralleling the three resistances 1' to W. Finally assuming the device 3 to occupy its fourth operative position, circuit may be traced from the right hand terminal of the motor armature to contact 9 and segment 9, thence to segment 10 and contact 10 to line L, thereby short-circuiting all of the armature resistances. Lastly, the energizing circuit of main switch 1 may be traced from line L through switch 2, thence through the winding of said switch 1 by conductor 19 to line L.

It is of course to be understood that the accelerating device 3 may be operable either after. stopping of the latter and means pro viding for restarting of the motor in any running position of said accelerating means.

2. In a motor controller, in combination, means operable to efiect acceleration of the motor and means governed by the position of said former means to render the same effective and inefiective with respect to said motor whereby the motor may be started in any operative position of said former means but accelerated only upon operation thereof.

3. In a motor controller, in combination, starting resistance, means controlling said resistance to accelerate the motor and means providing for starting of the motor with a given amount of said resistance in circuit therewith irrespectlve of the accelerating position of the former means.

4. In a motor controller,- in combination,

5. In a motor controller, in combination,

starting resistance, means movable to different positions forvarying the value of said resistance for motor control, and means operative upon closure of the motor circuit under certain conditions for rendering the value of the resistance in said circuit independent of the position of said former means.

6. In a motor controller, in combination, resistance for the motor circuit, means for varying the restrictive effect of said resistance with respect to the motor and means to render the former means inefiective with respect to said resistance whereby the motor may be started with a given restrictive effect of said resistance irrespective of the accelerating position of said former means but subject to subsequent variation of the restrictive effect of said resistance upon resetting and repeated operation of said former means.

7. In a motor controller, in combination, resistance for the motor circuit, means for varying the restrictive effect of said-resistance with respect to the motor, means acting upon interruption of the motor circuit to render the former means ineffective with respect to said resistance and requiring resetting to again subject said resistance to control by said former means and means for restraining the resetting of the second mentioned means pending resetting of said former means for a given restrictive effect of said resistance.

8. In comblnation, a motor, an accelerating device therefor, means acting upon interruption of the circuit of said motor to disconnect said device therefrom pending resetting of both said device and said means while permitting immediate restarting of said motor and means to delay resetting of .the former means pending resetting of said device.

9. In combination, a motor, an accelerating device therefor, and a switch to render said device efiective and ineffective with respect to said motor, said switch being releasable upon interruption of the motor circuit to render said devices inefiective and having a restraining windin controllable by said device to prevent its resetting except upon predetermined positioning of said device thereby permitting restarting of said motor free from the acceleratiii influence ofisaid device when in an accefierating position.

10. In combination, a motor, an accelerating device therefor and a switch to "render said device efiective and ineffective with respect to said motor, said switch being releasable upon interruption of the motor circuit to render said device ineffective and havinga restraining winding in series with said motor and controllable by Said device to prevent its resetting except upon "predetermined positioning of said devlce thereby permittingrestarting of said motor free from the accelerating influence of said device when in an accelerating position.

11'. In combination, a motor, an accelerating device therefor, and a switch adapted upon closure thereof torendersaid device effective with respect to said motor and upon release to render said device ineffective with respect thereto, said switch having an operating winding energizable upon comple-- tion of the motor circuit and deenergizable upon interruption of said circuit and further having a winding in series with said motor to restrain it against closure pending predetermined positioning of said device following interruption of the motor circuit.

"12. In a motor controller, in combination, sets of starting resistance, means for progressively paralleling and finally short circuiting said resistance sets for motor acceleration and means providing for starting of the motor with a given value of said resistance in circuit therewith irrespective of the accelerating position of said former means.

In witness whereof, I have hereunto subscribed my name.

RICHARD B. HUNTER. 

